Propelling and operating drive for trenchers



Sept. 2l, 1965' R. METAILLER PROPELLING AND OPERATING DRIVE FOR TRENCHERS 2 Sheets-Sheet 1 Filed D60. 5l, 1963 R METAILLER sept. 21, 1965 PROPELLING AND OPERATING DRIVE FOR TRENCHERS Filed DSG. 31, 1963 2 Sheets-Sheet 2 Un1ted States Patent O 3,206,877 PROPELLING AND DPERATING DRIVE FOR TRENCHERS Roger Metailler, 7 Ave. Ingres, Paris, France Filed Dec. 31, 1963, Ser. No. 339,056 Claims priority, application France, .lune 2, 1960, 828,898, Patent 1,267,198 2 Claims. (Cl. 37--90) This invention relates to a self-powered earth-digging machine of the type designed for excavating trenches and is a continuation-in-part of my copending U.S. patent application, Serial No. 112,960, filed May 26, 1961, now abandoned.

The self powered earth-digging machine comprises an engine for actuating both a drive means for propelling the machine and a drive means for operating the digging tool. The ratio of the resistances met by these two different drive means is known to vary considerably during the operation of the machine, according to the quality of the successive ground sections cut by the tool. Therefore a machine of this character will not operate in a reliable and satisfactory manner unless the power transmitted from the engine to these two drive means respectively is properly distributed.

It is the essential object of this invention to provide a self-powered machine for digging trenches which automatically provides a proper distribution of the engine torque to the machine propelling drive means and to the digging-tool drive means.

This machine is characterized by the combination of a main torque converter and of a secondary torque converter operatively interrelated to automatically distribute the engine torque to the machine propelling means and to the digging-tool drive means during the operative periods of the machine.

The features and advantages of this invention will become readily apparent from the following description, given hereafter by way of example with reference to the accompanying drawing, in which:

FIGURES 1 and 2 show in side elevational views the general arrangement of a machine of the type set forth in its operative and inoperative positions, respectively;

FIGURES 3 and 4 show an alternate embodiment of the machine; similarly in the operative and inoperative positions;

FIGURE 5 is a diagram illustrating the control system of this invention.

In the trencher illustrated in FIGS. 1 .and 2 of the drawings the digging tool proper consists of a bucket wheel 1. This conventional-type machine comprises a self-powered chassis frame 2 mounted on tires 3 or other appropriate translation system, as for example endless crawler belts. The bucket wheel 1 is carried by a frame 4 pivoted at 5 to the chassis frame 2. A control system 6 is provided for displacing the assembly of frame 4 and wheel 1' in a vertical plane about the pivot axis 5. A mechanism 7 transmits to the wheel 1 a rotation movement about the axis 8, as shown by the arrow f1. During the operation, the machine propelling means cause displacement of the complete machine in the direction of the arrow F2. The mechanisms controlling the movements in the direction of the arrows f1 and F2 are so designed as to operate simultaneously during the trench digging work. In the road driving position shown in FIG. 2 the tool 1 is raised above ground level and the mechanism 7 is not operated.

In the trencher illustrated in FIGS. 3 and 4, theI tool consists of a bucket carrier endless chain 9. A mechanism 10 drives the bucket chain in the direction of the arrow F3. Another mechanism drives the complete machine in the direction of the arrow F4. In the road driv- 3,206,877 Patented Sept. 21, 1965 ing position shown in FIG. 4 the tool 9 is raised above ground level and the mechanism 10 is not operated.

In the control system illustrated diagrammatically in FIG. 5 the engine 11 drives a main torque converter 12 which may for example be of the hydraulic variety. Output shaft 48 of main torque converter 12 transmits its torque and speed characteristics to pinion 13 and transmission shaft 19. The pinion 13 drives the toothed wheels 14, 15 housed in a case 16. The shaft 17 on which wheel 15 is keyed drives in turn a secondary torque converter 18 which may for example also be of the hydraulic variety. Output shaft 50 of secondary torque converter 18 transmits its specific torque and speed characteristics to a pinion 21 housed in a case 20. This pinion 21 drives in turn a double gear pinion 22, 23 mounted for free rotation on a shaft 24 journalled in the case 20, as shown. Pinion 23 in turn drives a toothed wheel 25 mounted for free rotation on a shaft 26. A double dog clutch 27 is mounted on shaft 26 so as to revolve bodily therewith while being free to slide axially therealong under the control of adequate means to be described presently.

The transmission shaft 19 is coupled to and drives a shaft 29 which may be considered as an extending end portion of main torque converter output shaft 48. End portion 29 revolves freely in the case 20 in axial alignment with the shaft 26. A toothed wheel 28 keyed to shaft 29 drives a wheel 30 revolving freely about a shaft 31 journalled in turn in the same casing 20. A single dog clutch 32 rotatably solid with this shaft 31 is adapted to slide axially therealong. A lever 33 fulcrumed intermediate its ends on a fixed pin 34 carried by the case 20 has two forked ends whereby the double dog-clutch 27 and single dog-clutch 32 may be caused to slide along their shafts 31 and 26 respectively. An output transmission shaft 37, driven from shaft 26, transmits the motion thereof to a gearbox 38, which in turn drives shafts 39, 40 and axles 41 and 42 or any other conventional mechanism for controlling the motion of the machine as shown by arrow F2 in FIGURE 2 or F4 in FIGURE 3.

The other output shaft 35 of case 20, which is driven from shaft 31, transmits its motion to another gearbox 36. This, in turn, `actuates through transmission coupling members 43, 44, 45 and 46 the driving or input sprockets for rotating the shaft 47 of digging tool 9 as shown by the arrow F1 of FIGURE 1 or F3 of FIGURE 3.

This control mechanism operates as follows:

To set the machine in its operative position, the forked lever 33 is pivoted in the counter-clockwise direction as viewed in FIGURE 5. The upper arm of lever 33 moves the single dog-clutch 32 in the direction of the arrow a to a first end position whereat the wheel 30 becomes rotatably solid with shaft 31 4and hence output shaft 35 coupled thereto. At the same time the lower arm of this fork 33 moves the double-dog clutch 27 in the direction of the arrow b to a first end position thereof causing shaft 26 to become rotatably solid with wheel 25. Thus, shaft 26, and hence output shaft 37, is driven independently of shaft 29. The shearing resistance of the ground which is to be overcome by an effort in the direction of the arrow f1 in FIG. 1, or F3 in FIG. 3, produces a variation in the velocity of rotation of the main torque converter output shaft 48 as a function of the characteristics of the main torque converter 12. This velocity of rotation decreases as the shearing resistance of the ground increases. The variation in speed of shaft 48 is transmitted to the secondary torque converter 18. Thus, the secondary torque converter transmits to pinion 21 and therefore ultimately to the machine propelling means 41, 42 a velocity of rotation and a torque that are proportional to the input velocity of the secondary torque converter 18. This torque produces an effort directed according to the arrow F2 of FIG. 1, or F4 of FIG. 3.

The maximum engine power output .available can be transmitted to the tool 1 or 9 when the shearing resistance of the ground increases. In this case the torque converter 18 is discharged and cannot drive the machine in translation. As the tool is no more urged in the direction F2 or F4, it does not penetrate into the material or ground being dug, and the resistance along f1, or F3 decreases as well as the power absorbed by the shaft 48. Therefore, the velocity of rotation of the output shaft 48 of the main torque converter 12 and therefore of the secondary torque converter 18 increases. The converter 18 will then transmit to the machine propelling means 41, 42 an effort directed according to F2 and F4 which causes the tool 1 or 9 to penetrate into the material or ground to be dug.

If the shearing resistance resulting from the ground structure is relatively moderate, the characteristics of main torque converter 12 are such that output shaft 48 tends to revolve at maximum speed, `and in this case the secondary torque converter 18 will transmit a maximum penetration speed to the digging tool for operation in the direction F2 or F4.

Thus, the control system of this invention ensures an automatic distribution of the torques among the two mechanisms, as a function of the resistance resulting from the ground structure or conditions. Consequently, the velocity of operation is set automatically in proportion to the ground resistance.

To set the machine in its road driving position (without tool operation), the lever 33 is pivoted in the clockwise direction as viewed in the diagram of FIG. 5. The lower forked arm of this lever moves the double-dog clutch 27 in the direction of the arrow lc to a second end position, thus causing the shaft 26 to revolve bodily with shaft 29. At the same time the upper forked arm of this lever moves the single-dog clutch 32 in the direction of the arrow d to a second end position thereof thus disengaging the shaft 31 from wheel 30. In this case the output transmission shaft 35 to the digging tool is not driven. Main torque converter 12 only drives the axles 41 and 42, and the secondary torque converter 18 revolves freely since wheel 25 which it drives will be revolving freely on shaft 26. Thus, the machine is actuated only through the operation of the main torque converter 12.

Although the present invention has been described in conjunction with preferred embodiments, it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the invention, as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the invention and appended claims.

The embodiments of the invention in which an exclusive privilege or property is claimed are defined as follows:

1. A self-powered earth-moving machine for digging trenches, comprising: an engine; a main torque converter driven from said engine; an output shaft of said main torque converter having an end portion coupled thereto; a toothed wheel rigidly carried by said end portion of said output shaft of said main torque converter; a second shaft mounted in axial alignment relative to said end ,portion of said main torque converter; a toothed wheel mounted for free rotation on said second shaft; a double dog-clutch slidably mounted on said second shaft; a shift fork connected to said double dog-clutch for movement of said double dog-clutch along said second shaft in a direction to an operative iirst end position, wherein said second shaft is rotatably solid with said toothed wheel mounted for free rotation on said second shaft, and an opposite direction to a second operative end position, wherein said second shaft is rotatably solid with said toothed Wheel carried by said end portion of said main torque converter; a Iirst gear box driven by said second shaft; a mechanism controlling the motion of said machine which is operated by said rst gear box; a secondary torque converter; a positive direct drive constituting a mechanical coupling between said output shaft of said main torque converter and said secondary torque converter; a third shaft constituting the output shaft of said secondary torque converter; another positive drive for rotatably coupling said third shaft with said toothed wheel of said second shaft; a fourth shaft; a toothed wheel mounted for free rotation on said fourth shaft and driven by said toothed wheel carriedfby the end portion of the output shaft of the main torque converter; a single dogclutch slidably mounted on saidofourth shaft; said shift fork connected to said single dog-clutch for movement of said single dog-clutch along said fourth shaft in a direction to an operative first end position, wherein said fourth shaft is rotatably solid with said toothed wheel mounted for free rotation on said fourth shaft; a second gear box driven by said fourth shaft; a digging tool actuated by said second gear box; said shift fork being a double shift fork pivotally mounted between said second and fourth shaft with the opposite ends connected to said single and double dog-clutches, respectively to control the shifting movements of said dog-clutches between their respective rst and second end positions.

2. A self-powered earth-moving machine as set forth in claim 1, wherein at least one of said torque converters comprise a hydraulic torque converter.

References Cited by the Examiner UNITED STATES PATENTS 2,084,887 6/37 Benett 37 2,749,756 6/56 George 37-86 FOREIGN PATENTS 1,059,17 1 6/59 Germany.

BENJAMIN HERSH, Primary Examiner. 

1. A SELF-POWERED EARTH-MOVING MACHINE FOR DIGGING TRENCHES, COMPRISING: AN ENGINE; A MAIN TORQUE CONVERTER DRIVEN FROM SAID ENGINE; AN OUTPUT SHAFT OF SAID MAIN TORQUE CONVERTER HAVING AN END PORTION COUPLED THERETO; A TOOTHED WHEEL RIGIDLY CARRIED BY SAID END PORTION OF SAID OUTPUT SHAFT OF SAID MAIN TORQUE CONVERTER; A SECOND SHAFT MOUNTED IN AXIAL ALIGNMENT RELATIVE TO SAID END PORTION OF SAID MAIN TORQUE CONVERTER; A TOOTHED WHEEL MOUNTED FOR FREE ROTATION ON SAID SECOND SHAFT; A DOUBLE DOG-CLUTCH SLIDABLE MOUNTED ON SAID SECOND SHAFT; A SHIFT FORK CONNECTED TO SAID DOUBLE DOGUCLUTCH FOR MOVEMENT OF SAID DOUBLE DOG-CLUTCH ALONG SAID SECOND SHAFT IN A DIRECTION TO AN OPERATIVE FIRST END POSITION, WHEREIN SAID SECOND SHAFT IS ROTATABLY SOLID WITH SAID TOOTHED WHEEL MOUNTED FOR FREE ROTATION ON SAID SECOND SHAFT, AND AN OPPOSITE DIRECTION TO A SECOND OPERATIVE END POSITION, WHEREIN SAID SECOND SHAFT IS ROTATABLY SOLID WITH SAID TOOTHED WHEEL CARRIED BY SAID END PORTION OF SAID MAIN TORQUE CONVERTER; A FIRST GEAR BOX DRIVEN BY SAID SECOND SHAFT; A MECHANISM CONTROLLING THE MOTION OF SAID MACHINE WHICH IS OPERATED BY SAID FIRST GEAR BOX; A SECONDARY TORQUE CONVERTER; A POSITIVE DIRECT DRIVE CONSTITUTING A TORQUE CONVERTER; A POSITIVE DIRECT DRIVE CONSTITUTING A MAIN TORQUE CONVERTER AND SAID SECONDARY TORQUE CONVERTER; A THIRD SHAFT CONSTITUTING THE OUTPUT SHAFT OF SAID SECONDARY TORQUE CONVERTER; ANOTHER POSITIVE DRIVE FOR ROTATABLY COUPLING SAID THIRD SHAFT WITH SAID TOOTHED WHEEL OF SAID SECOND SHAFT; A FOURTH SHAFT; A TOOTHED WHEEL MOUNTED FOR FREE ROTATION ON SAID FOURTH SHAFT AND DRIVEN BY SAID TOOTHED WHEEL CARRIED BY THE END PORTION OF THE OUTPUT SHAFT OF THE MAIN TORQUE CONVERTER; A SINGLE DOGCLUTCH SLIDABLY MOUNTED ON SAID FORUTH SHAFT; SAID SHIFT FORK CONNECTED TO SAID SINGLE DOG-CLUTCH FOR MOVEMENT OF SAID SINGLE DOG-CLUTCH ALONG SAID FOURTH SHAFT IN A DIRECTION TO AN OPERATIVE FIRST END POSITION, WHERIN SAID FOURTH SHAFT IS ROTATABLY SOLID WITH SAID TOOTHED WHEEL MOUNTED FOR FREE ROTATION ON SAID FOURTH SHAFT; A SECOND GEAR BOX DRIVEN BY SAID FOURTH SHAFT; A DIGGING TOOL ACTUATED BY SAID SECOND GEAR BOX; SAID SHIFT FORK BEING A DOUBLE SHIFT FORK PIVOTALLY MOUNTED BETWEEN SAID SECOND AND FOURTH SHAFT WITH THE OPPOSITE ENDS CONNECTED TO SAID SINGLE AND DOUBLE DOG-CLUTCHES, RESPECTIVELY TO CONTROL THE SHIFTING MOVEMENT OF SAID DOG-CLUTCHES BETWEEN THEIR RESPECTIVE FIRST AND SECOND END POSITIONS. 